Prevalence of Cryptosporidium infection in calves in France

Two multicentre surveys were conducted in France to estimate the prevalence of Cryptosporidium infection in calves using qualitative ELISA for detecti on of Cryptosporidium coproantigens and oocysts. The first survey involved 4-12-day-old calves in six dairy-calf distribution centres, collecting calv es from seven Administrative Regions (Aquitaine, Bretagne, Franche-Comte, L orraine, Normandie, Nord, Pays de Loire). For each region, 20 calves were s elected every month for 12 consecutive months (October 1995-September 1996) . Prevalence of Cryptosporidium infection was 17.9% (Confidence Intervals ( C.I.) 95%=[16.1%; 19.8%]) among the 1628 selected calves, of which only 5.3 % had diarrhoea. The second survey conducted between November 1995 and May 1996 involved 4-21-day-old calves examined by veterinary practitioners who selected 189 livestock farms of dairy- or suckler-type in ten Administrativ e Departments (Allier, Cantal, Creuse, Doubs, Ille-et-Vilaine, Maine-et-Loi re, Manche, Pas-de-Calais, Saone-et-Loire, Vendee). Cryptosporidia were det ected in 105 (55.6%) of the farms. Among the 440 calves examined, of which 398 (90.5%) presented diarrhoea, cryptosporidia were found in 191 animals, i.e. a prevalence of 43.3% (C.I. 95%=[38.8%; 48.0%]). Breed of calves and t ype of housing had very little impact on prevalence in this survey. Some re gional variations could be noticed, even if cryptosporidia infection is wid espread. Monthly variations could be related to seasonal peaks in calving w ith a lower infection rate during summer. (C) 2000 Elsevier Science B.V. Al l rights reserved.